Cancer patients’ motivation for participating in a phase I clinical trial do not reflect likely outcomes

medwireNews: Study findings highlight the gap between patient expectations of participation in a phase I trial of a novel anticancer agent and the likelihood of clinical benefit.

“[W]e found that more than 80% of patients enrolling in early clinical oncology trials were motivated by the prospect of a clinical benefit”, write Udai Banerji, from Royal Marsden NHS Foundation Trust in London, UK, and co-authors in Cancer.

Before consultation, over 40% of patients expected tumour shrinkage and 14% believed in the possibility of a cure but the team emphasizes that “[t]hese rates conflict with the typical phase 1 response rates of 4% to 20%, and this discrepancy demonstrates the challenges facing patients and healthcare professionals during their interactions in phase 1 studies.”

In all, 396 patients, most of whom had gastrointestinal or gynaecological tumours or lung cancer, completed a pre-consultation questionnaire when attending a clinic to discuss participating in their first phase I trial and 301 patients also responded to a shorter survey after their visit.

Motivation for participation was primarily tumour shrinkage (83.5%), followed by absence of alternative treatment options (56.0%), following their physician’s recommendation (44.2%), hoping research will benefit other patients (38.0%) and family wishes (24.4%).

Analysis showed that older patients were more likely motivated by their physician and research benefits than younger individuals, while patients who left education before age 17 years were more likely to state tumour shrinkage, lack of alternative options, family wishes or research benefits than those with more education.

In addition, gastrointestinal cancer patients were significantly more likely than those with other types of tumour to state no other treatments being available as their motivation. “This could reflect that these tumor types may have fewer standard lines of treatment available in comparison with others such as breast and gynecological cancers”, the researchers suggest.

At baseline, 42.7% of patients believed their tumours would shrink during the trial and this rose to 46.8% after their consultation, with patients also becoming more likely to consider that their tumours might grow (0.3 to 1.3%) or remain the same (6.3 to 10.6%). The proportion of patients who stated they did not know fell from 50.8% to 41.2%.

“It is tempting to interpret this as patient misinterpretation of previous discussions with healthcare professionals or a lack of information provided to patients throughout their cancer journey and to conclude that as a result we should inform our patients better”, Udai Banerji et al write.

“An alternative explanation is that this subset of patients, despite having been exposed to this information, have chosen to maintain unrealistic hope”, they suggest, noting the need to balance reiterating a poor prognosis with the “importance of human hope.”

Most patients before and after consultation expected moderate side effects (70.7 vs 77.1%) and when the 286 patients who had previously undergone chemotherapy were asked about their expectation of side effects in a phase I trial, most said that adverse events would be the same as those experienced during earlier treatment (60.9 vs 54.1%).

Consultation resulted in an increase in the number of patients who expected to visit the hospital once a week during a trial (from 49.7 to 93.0%), but this did not put patients off participating, with the number willing to enter a phase I trial rising from 71.5% to 84.3%.

“Thus, our current first consultation in the phase 1 unit does not significantly change expectations but does clarify the understanding of the time commitment involved”, the authors suggest.

“These results will be reviewed by our focus groups to find ways to improve these discussions”, they conclude. “It would be interesting to repeat this study at a later time point to assess how perceptions change after the receipt of treatment within a study.”